Apparatus for spraying refractory lining

ABSTRACT

A lining gun for spraying refractory lining on the interior of ladles and the like which includes two elongate concentrically disposed conduits through which dry refractory material and water are respectively passed at one end and sprayed through mixing nozzles at the opposite end. Each conduit includes a rotary coupling immediate its length and cooperates with a motor driven ring and pinion assembly which rotates the lower portion of the apparatus including the nozzles for circular spraying.

Unite States Patent Hans Mar. 19, 1974 1 APPARATUS FOR SPRAYING3.460.988 8/1969 Kennedy, Jr. et al 239/227 x REFRACTORY LINING [76]Inventor: Jan F. Haas, 1861 Stage Court Dr., Pmnary ExammerAnen NKnowles Allison Park, Pa. 15101 Filed: Jan. 24, 1973 Appl. No.: 326,423

References Cited UNITED STATES PATENTS 3o 4/1937 Frede e131 ..239/227 349/1961 Grant, 11 29/2714 1/1969 Ajnefors 239/264 x AssistantExaminer-Andres Kashnikow Attorney, Agent, or Firm--Char1es F. Duffield[57] ABSTRACT A lining gun for spraying refractory lining on theinterior of ladles and the like which includes two elongateconcentrically disposed conduits through which dry refractory materialand water are respectively passed at one end and sprayed through mixingnozzles at the opposite end. Each conduit includes a rotary couplingimmediate its length and cooperates with a motor driven. ring and pinionassembly which rotates the lower portion of the apparatus including thenozzles for circular spraying.

4 Claims, 4 Drawing Figures APPARATUS FOR SPRAYING REFRACTORY LININGBACKGROUND OF INVENTION In the iron and steel industry, such deep walledrefractory bodies as ladles, soaking pits and furnaces are subjected toextremely high temperatures over long periods of time. Such hightemperatures cause deterioration of the refractory linings of thebodies. After the lining has deteriorated to a certain point, the liningmust be replaced or repaired before the ladle, etc. can be further used.

The interior surface of the ladles can be repaired in a number ofdifferent ways. One common repair which has come into common practice isto spray a protective coating of refractory material onto the interiorof the ladle.

Refractory spraying apparatus for ladles and the like which areavailable today are all essentially hand operated devices. A man isrequired to enter the ladle and to hand spray the refractory materialabout theinterior. Hand spraying of the ladles is an extremely timeconsuming job. Additionally, the quality of the job accomplished is onlyas good as the skill of the laborer.

A further problem encountered in hand spraying of ladles is the coolingtime required before a workman can enter the ladle or furnace. Forexample, a ladle of ordinary and common size which has just been takenout of use will require between six to twelve hours to cool before aworkman can enter the ladle to spray a new lining. The turn around timebetween cooling, spraying and drying of a ladle can be extremelydetrimental to production rates in a steel mill and costly as well.

There is a requirement in the industry for a ladle spraying apparatuswhich will operate automatically to deposit the lining in a controlledmanner and also one which can spray on the lining immediately or shortlyafter the ladle is taken out of service without having to wait for theladle to cool and be hand sprayed.

OBJECTS AND SUMMARY OF INVENTION It is the object of the presentinvention to provide a lining gun for spraying a refractory lining onthe interior of ladles and the like which operates automatically and ina controlled manner in depositing the lining and also which may beemployed for hot replacement of the sprayed refractory material within ahot ladle.

The foregoing object is carried out by the lining gun of the presentinvention by means of two elongate conduits, one of which is disposedconcentric within the other. The first and outer conduit includes anentrance end through which dry refractory material is air conveyed toopposed mixing nozzles at the opposite end of the conduit. The secondand inside conduit includes an entrance end through which a wettingagent for the refractory material is passed and terminates atitsopposite end in communication with the mixing nozzle wherein thewetting agent is mixed with the dry refractory material to provide thewetted material which is sprayed.

The inner and outer conduits each include rotary coupling means whichpermit rotation of the lower portions of each of the conduits attachedto the spray nozzles relative to the upper portions thereof. Motor meansattached to the upper stationary portion of the outer conduit drives apinion which in turn drives a ring gear attached to the lower outerconduit to revolve the mixing nozzles.

In a specific embodiment, a stabilizing bearing is journaled upon thelower portion of the outer conduit adjacent the coupling. Thestabilizing bearing is secured to a bearing carrier which is rigidlysecured to the upper stationary portion of the outer conduit to providerigidity to the outer conduit across the rotary coupling.

The lining gun includes a carriage assembly at its upper portion bywhich the entire assembly is suspended within and for axial movementthrough the interior of the ladle or furnace. The entire assembly ismoved axially from the bottom of the ladle toward the top thereof as thespray nozzles are rotated to completely and entirely spray the interiorof the ladle or furnace.

Other objects and advantages of the present invention will becomeapparent to those skilled in the art from the detailed description ofthe invention which follows taken in conjunction with the drawings.

DESCRIPTION OF DRAWINGS FIG. I is a side view of the entire lining gunof the present invention shown in position in use with a ladle;

FIG. 2 is a side view of the upper portion of the lining gun of thepresent invention;

FIG. 3 is a side view of the lower portion of the lining gun of thepresent invention; and

FIG. 4 is a side view partially in section of the details of the flowsplitter employed in the lining gun of the present invention.

DETAILED DESCRIPTION OF INVENTION The gun for spraying refractory liningof the present invention is shown in FIG. 1 in its postion of use. Theentire assembly 10 is designed to be suspended above a ladle 14 by meansof a crane hook l2 and cable 13 which engage a carriage assembly 1 1supporting the remainder of the apparatus.

Generally, the lining apparatus includes an elongate first or outerconduit 15 through which a dry refractory material is air conveyed to apair of opposed mixing discharge nozzles l7 at the lower end of theconduit. A similar second or inner conduit disposed within the firstconduit 15 is connected to a water supply line 9 and extends to themixing discharge nozzles 17 at which point the water is mixed with thedry refractory material and sprayed from the nozzles.

As will be described in more detail hereinafter, both the inner andouter conduits include rotary couplings which permit the lower ends ofthe conduits connected to the discharge nozzles 17 to be rotatedrelative to the top portions of the conduits. These rotary couplingsoperate in conjunction with a drive mechanism 18 which causes the lowerportion of the mechanism, including the nozzles 17, to be rotated whilethe upper portion of the assembly remains stationary.

During operation, the mixed material is sprayed from the nozzles whilethe nozzles rotate to present a circular spraying pattern.Simultaneously with the rotation of the nozzles, the entire assembly isslowly raised upwardly through the ladle covering the entire innersurface of the ladle with the refractory material.

The details of the refractory spraying mechanism of the presentinvention are shown in FIGS. 2-4. The

body of the lining gun is formed of a first elongate conduit whichextends substantially throughout the entire length of the gun. The upperportion of the first conduit 15 is enclosed by a pipe cap 23 and issecured to a crossbar 19 by means of a U-clamp 20. The crossbar 19 is,in turn. welded between a pair of vertical support arms 21 which arelikewise welded to the main carriage beam. In this manner. the maincarriage assembly provides the supporting structure for the firstconduit 15 and all of its related plumbing and hardware while the gun isbeing suspended for use over a ladle.

The outer conduit 15 also includes an entrance port 41 disposed in theupper extremities of the conduit. The entrance port 41 is formed by apipe welded over an aperture in the side wall of the conduit 15. Theport 41 terminates in a suitable pipe coupling 42 which isinterconnected with the refractory material supply line 16.

A wear sleeve 43 is positioned around the inner conduit 22 adjacent thedischarge end of the port 41. The wear sleeve 43 protects the surface ofthe inner conduit 22 from the abrading action of the refractorymaterials passing through the entrance port 41.

The lining gun also includes an inner or second conduit 22. The conduit22 is disposed within and concentric of the first conduit 15. The upperend of the conduit 22 extends through a sealing packing gland 24 whichis fitted into the pipe cap 23.

A rotary coupling 25 is provided and is connected to one end of theinner conduit 22. The opposite end of the rotary coupling is connectedthrough a plumbing tee to a horizontal supply line 26. The supply line26 is secured in place and against rotation through apertures 28 in thevertical support arms 21 of the carriage assembly.

The lower end of the outer or first conduit 15 terminates in a pipe cap29 which encloses the bottom end of the conduit. Immediately above thepipe cap 29 are disposed a pair of opposed discharge mixing nozzles 17.

The discharge nozzles 17 include a pair of entrance ports 30 which aresuitably welded over cutout openings in the side walls of the firstconduit 15. A water flow mixer assembly 31 is threaded onto each of theentrance ports 30. In turn, a discharge nozzle 32 is threaded into thewater flow mixer assembly 31.

The lower end of the inner conduit 15 terminates in a flow splitter 33.The flow splitter 33, as may be seen in FIG. 3 and in detail in FIG. 4,is positioned in the lowermost portion of the first conduit 15 and isheld in place by abutment with the pipe cap 29.

The flow splitter 33 includes an internal passageway 34 through the bodyof the flow splitter. The upper end 35 of the passageway is threaded andreceives the threaded lower end of the inner conduit 22.

The opposite end of the passageway 36 is formed at a right angle to theaxis of the conduit 15 and is likewise threaded to receive a pipe nipple37 which passes through a suitable aperture in the wall of the outerconduit 15. A plumbing tee 38 is provided on the pipe nipple 37. In alike manner, a pair of flexible hoses 39 are connected to the plumbingtee and to the respective water flow mixer assemblies 31 to complete theflow path through the inner conduit 22.

The flow splitter 33 further includes two opposed faces 40. The opposedfaces are turned generally perpendicular to the longitudinal axis of thenozzles 32. The faces converge at a point above the entrance port 30 andflare downwardly and outwardly to a terminal point below the entranceport 30. The flare of the flow splitter serves to evenly deflect therefractory material to the nozzle assemblies.

A further rotary coupling 44 is provided intermediate the ends of thefirst conduit 15 as may be seen in FIG.

. 3. The rotary coupling permits the lower portion of the conduit 15 tobe rotated while the upper portion thereof is held stationary. Thecoupling is airtight to prevent escape of material passing through theconduit.

The lower portion of the outer conduit 15 and its included dischargenozzle assembly is driven in a rotary manner by means of a driveassembly 18. The drive assembly 18 includes a pair of opposedstabilizing plates 45 which are suitably welded to the outer surface ofthe outer conduit 15 at a point immediately above the rotary coupling44. The lower portions of the stabilizing plates 44 extend downwardly toa point below the rotary coupling 44.

A horizontal bearing carrier plate 46 is provided and includes anaperture within the plate through which the outer conduit 15 extends.Either end of the bearing carrier plate 46 extend outwardly and areinterconnected with the lower ends of the stabilizing plates 45. A splitjournal bearing 47 is positioned around the conduit 15 immediately belowthe horizontal carrier plate 46. The journal bearing 47 isinterconnected to the carrier plate 46 by angle races 48. Thearrangement of the stabilizing plates 45, bearing carrier 46 and journalbearing 47 add stability and reinforcement against side loads on theouter conduit 15 across the rotary coupling 44. A ring gear 49 isdisposed concentrically around the outer conduit intermediate the rotarycoupling 44 and journal bearing 47. The ring gear 49 is secured in placeon a flange 50 which is welded to the outer circumference of the conduit15. A suitable air motor 51 is mounted on one of the stabilizing plates45. The air motor includes a drive shaft 52 and a pinion 53 for drivingthe ring gear 49 and consequently revolving the nozzles.

Two flange coupling assemblies 54 and 55 are provided along the lengthof the outer conduit 15. These coupling assemblies aid in fabricationand assembly of the outer and inner conduits.

In operation, a dry refractory material is air conveyed through the feedline 16 and downwardly through the outer conduit and discharged past theflow mixer assemblies through the discharge nozzles 32. As this isoccurring, a suitable wetting agent for the dry refractory material suchas water, is passed through the inner conduit 22 to the flow mixerassembly. The water flow mixer assembly 31 includes a plurality ofinternal orifices around the inner circumference of the mixer assemblywhich sprays the water into the passing dry refractory material to forma mixed wet spray material.

Once the refractory material has begun discharging, operation of thedrive mechanism 18 is initiated to impart rotation to the opposednozzles. Likewise, the entire assembly will be slowly moved upwardly inthe ladle to assure complete coverage of the inner surface of the ladle.

It has been found appropriate to angle the nozzles downwardly at anappropriate angle of six to seven degrees. This angulation helps assurecoverage of the bottom and the convergence of the bottom with the wallsof the ladle. It has also been found that an appropriate speed ofrotation for the nozzles is approximately from one to three revolutionsper minute.

From the foregoing description, it will be appreciated that the presentinvention provides a lining gun which provides for automatic spraying oflining on ladies and the like and also a lining gun which may be used inconjunction with lining of hot ladles.

The lining gun assembly of the present invention has been described inrespect to particular embodiments thereof. it will be appreciated,however, to those skilled in the art that modification may be made inthe method and apparatus according to the invention without exceedingthe ambit of its spirit and scope.

I claim:

1. A lining gun for spraying a refractory lining on the interior of deepwalled refractory bodies such as ladles and the like comprising:

a first elongate conduit having an entrance end through which dryrefractory material is air conveyed and terminating at its opposite endin a mixing discharge nozzle through which the refractory material issprayed;

a second elongate conduit disposed within and concentric of the firstconduit and including an entrance end for receiving a wetting agent forthe refractory material and terminating at its opposite end incommunication with the mixing nozzle;

first and second rotary coupling means connected to the first andsecondconduits respectively intermediate their entrance ends and thedischarge nozzle permitting relative rotary motion between the entranceends of the conduits and the discharge nozzle; and

drive means for driving the discharge nozzle in a rotary manner wherebythe nozzle may be drawn axi ally through the refractory body as thenozzle is rotated and refractory material sprayed therefrom to uniformlycoat the interior surface thereof.

2. The lining gun of claim 1 wherein the mixing discharge nozzleincludes two opposed orifices and further including means disposedadjacent each orifice and centrally of the first conduit to divide theflow of dry refractory material equally between each orifice.

3. The lining gun of claim 1 wherein the drive means includes a ringgear carried by the first conduit intermediate the coupling means andthe discharge nozzle; motor means carried by the first conduit oppositethe coupling means and pinion drive means interconnecting the motormeans and the ring gear.

4. The lining gun of claim 3 further including bearing means secured tothe first conduit intermediate the coupling means and discharge nozzleand bearing carrier means interconnecting the bearing means and thefirst conduit at a point opposite the coupling means from the bearingmeans to maintain alignment of the first conduit across the couplingmeans.

1. A lining gun for spraying a refractory lining on the interior of deepwalled refractory bodies such as ladles and the like comprising: a firstelongate conduit having an entrance end through which dry refractorymaterial is air conveyed and terminating at its opposite end in a mixingdischarge nozzle through which the refractory material is sprayed; asecond elongate conduit disposed within and concentric of the firstconduit and including an entrance end for receiving a wetting agent forthe refractory material and terminating at its opposite end incommunication with the mixing nozzle; first and second rotary couplingmeans connected to the first and second conduits respectivelyintermediate their entrance ends and the discharge nozzle permittingrelative rotary motion between the entrance ends of the conduits and thedischarge nozzle; and drive means for driving the discharge nozzle in arotary manner whereby the nozzle may be drAwn axially through therefractory body as the nozzle is rotated and refractory material sprayedtherefrom to uniformly coat the interior surface thereof.
 2. The lininggun of claim 1 wherein the mixing discharge nozzle includes two opposedorifices and further including means disposed adjacent each orifice andcentrally of the first conduit to divide the flow of dry refractorymaterial equally between each orifice.
 3. The lining gun of claim 1wherein the drive means includes a ring gear carried by the firstconduit intermediate the coupling means and the discharge nozzle; motormeans carried by the first conduit opposite the coupling means andpinion drive means interconnecting the motor means and the ring gear. 4.The lining gun of claim 3 further including bearing means secured to thefirst conduit intermediate the coupling means and discharge nozzle andbearing carrier means interconnecting the bearing means and the firstconduit at a point opposite the coupling means from the bearing means tomaintain alignment of the first conduit across the coupling means.